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1. Evaluate the changes Dore-Dore has made in its children's knitwear division. How does the performance of the traditional operations and the cellular manufacturing system differ? For example, how does work-in-process inventory change when cells are implemented? Traditional Operations: Under traditional operations, Doré-Doré’s production batch size in sewing, on average, was 200 pieces of the same style and color, with an average of eight different sizes within a batch. The knitwear sewing contained 55 sewing machines installed and was staffed by 42 workers (Exhibit 7). The additional machines were either specialty machines used for occasional operations or extra machines used in periods of peak demand. The sewing machine operators worked eight hours per day, five days per week. Sewing an average knitwear garment took 10 minutes of actual labor. Cellular Manufacturing: Cellular manufacturing significantly reduced many types of waste present in the traditional sewing process and resulted in delivery time falling from 15 days to 1 day. Given a flow rate of 2,000 garments per day work-in-progress fell from 30,000 to 2,000 units, improving annual work-in-process turns from 16X to 240X. According to Exhibit 4, the work-in-progress inventory fell by an estimated 1.23FF million and holding costs by 275,000FF . Comparison: The grid layout by machine type of the traditional system took no account of garment dependent workflow variability and resulted in the unnecessary movement of inventory. By contrast the garment-specific cell design reduced product movement and cross-trained operators who could switch tasks, which helped balance work-flow (Exhibit 6). 2. What changes are required to ensure successful implementation of cellular manufacturing? Is worker cross-training necessary?

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Page 1: dore dore

1. Evaluate the changes Dore-Dore has made in its children's knitwear division. How

does the performance of the traditional operations and the cellular manufacturing

system differ? For example, how does work-in-process inventory change when cells are

implemented?

Traditional Operations: Under traditional operations, Doré-Doré’s production batch size in

sewing, on average, was 200 pieces of the same style and color, with an average of eight different

sizes within a batch. The knitwear sewing contained 55 sewing machines installed and was

staffed by 42 workers (Exhibit 7). The additional machines were either specialty machines used

for occasional operations or extra machines used in periods of peak demand. The sewing

machine operators worked eight hours per day, five days per week. Sewing an average knitwear

garment took 10 minutes of actual labor.

Cellular Manufacturing: Cellular manufacturing significantly reduced many types of waste

present in the traditional sewing process and resulted in delivery time falling from 15 days to 1

day. Given a flow rate of 2,000 garments per day work-in-progress fell from 30,000 to 2,000

units, improving annual work-in-process turns from 16X to 240X. According to Exhibit 4, the

work-in-progress inventory fell by an estimated 1.23FF million and holding costs by 275,000FF .

Comparison: The grid layout by machine type of the traditional system took no account of

garment dependent workflow variability and resulted in the unnecessary movement of inventory.

By contrast the garment-specific cell design reduced product movement and cross-trained

operators who could switch tasks, which helped balance work-flow (Exhibit 6).

2. What changes are required to ensure successful implementation of cellular manufacturing? Is

worker cross-training necessary?

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Reorganization: The knitwear factory was currently organized by machine typ. For example, all button

hole machines were located in one area. Batches of partially-completed product were moved in

wheeled bins by floor supervisors or material handlers to the next required operation.

Crisis Management: If a machine in a cell broke down, it would have to be quickly repaired or replaced;

if possible, during the repair period, the worker would move to another machine within the cell to

continue working. Encouraged to act autonomously with regard to work methods, the workers

rearranged the cell in a new one evening after management and other workers had gone home.

Cross-Training: At first, the team tried to assign work using traditional methods, with each worker

specializing by task. This system made the sweatshirts well but was difficult to adapt to the next style

assigned to the cell.

Operation Layout: The cellular manufacturing system changed the entire layout of the operation as the

placement of machines, workers, and batch flow had originally been designed by ITF in a horseshoe

shape. The cell workers soon found this cumbersome for two reasons: first, the horseshoe worked best

if the production flow was unidirectional, whereas in the Doré-Doré cell, items were frequently passed

back to a previous machine for additional operations or rework; and second, the workers wanted to be

able to face each other to facilitate communication.

Conflict Resolution: Another traditional supervisory role was the resolution of relationship problems

between workers. In view of the autonomous nature of the teams, workers were provided training in

solving these types of problems. Conflicts were to be addressed first within the cell. For the first

experimental cell, ITF unwittingly chose two workers who were ardent enemies. DD decided to go ahead

with the chosen six members, but soon discovered that the two had difficulty working together. On its

own, the team decided to address the problem.

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3. What is Dore-Dore's motivation for converting to cells? Should the company continue with its plans for complete implementation of cells in children's knitwear? If not, which knitwear products (if any) should be manufactured in cells?

Autonomy of Workers: A key principle underlying the cell concept was that the groups were

autonomous, managing their own time, distribution of work, and work-flow. In contrast, in a

traditional batch production system such as that currently used by DD, each worker repeatedly

performed a single, specific task on each garment in a large batch of identical items, thereby

developing an expertise and a rhythm that fostered high levels of speed, productivity, and

product uniformity (see Exhibit 18).

Loyalty of Workers: Teams remained together unless someone left the factory. When a worker

was absent, the rate of output dropped. If the absence was long, the group could decide whether

it would accept an outside volunteer. In the first cell, when one team member went on maternity

leave, the five remaining members decided not to replace her, as she had promised to return.

Emphasizing the tremendous rise in loyalty by cell members, Marguet noted that the worker had

curtailed the length of her maternity leave to return to the cell.

Reduction in Delivery Time: The average sewing throughput time of a garment dropped from

15 working days to 1 working day by converting sewing department setup from traditional to

cellular.

WIP Reduction: Work-in progress was reduced from 720 to 48 by converting from traditional

to cellular setup. Additionally, there was reduced idle time and hence an increase in labor

utilization as well as machine utilization.

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4. Should Dore Dore implement cells in its hosiery production area? If so, would you suggest the changes to the cell design as currently proposed by M. Enfert? If not, what alternative approaches could Dore-Dore take to address the concerns M. Marguet raises

in the case?

The implementation of cells in hosiery production would be far more complicated than in

knitting production. The production of hosiery requires four distinct operations, not all of which

are compatible with the cell design. However, considering that only three out of four of the

processes are compatible with the cell model, in addition to other reasons, I would not

recommend the adoption of M. Enfert’s plan. If Enfert is correct, manufacturing throughput

time will fall to one week and finished goods hosiery inventory would drop 30-40%, however,

this improvement is marginal (and possibly incorrect) considering the potential losses sustained

through the use of the cell system. Additionally, one key consideration is budget limitations:

designing the cell was that ironing required an expensive (350,000-800,000FF per machine),

high-capacity, extremely specialized machine. We do not have much information regarding the

company’s budget. My other concern is that Enfert believes the teams should not be completely

cross-trained. By not implementing cross-training, the hosiery department would not reap the

benefits outlined in Question 3: autonomy of workers, loyalty of workers, loyalty of workers,

reduction in delivery time, and work-in-progress reduction. Coming from a more practical

standpoint, it would simply be too difficult to implement this system, which would operate

differently than the cell system in the knitting department, to two separate divisions of the

company at once. If Enfert’s plan is to be tested, it should be tested well after the

implementation of the cell system in the knitting operation, which will serve as a trial to its

effectiveness.